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Release 19April 2018
NIST Standard Reference Database 101
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III.G.1.a.

Comparison of levels of theory for O-O


Click on an entry for a histogram of the values.
The subscript refers to how many bonds of that type have been calculated.
average calculated bond lengths (Å)
Methods with predefined basis sets
semi-empirical AM1 1.1948
26
PM3 1.3205
26
PM6 1.2668
40
composite G2 1.3061
35
G3 1.3049
37
G3B3 1.3371
38
G3MP2 1.2697
8
G4 1.3236
37
CBS-Q 1.2945
36

average calculated bond lengths (Å)
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
hartree fock HF 1.3487
35
1.3930
35
2.0068
36
1.3635
35
1.3000
43
1.3081
36
1.2905
31
1.2903
37
1.2980
35
1.2987
36
1.3053
11
1.1579
1
1.2948
45
1.2930
51
1.2990
36
1.2987
36
1.2793
29
1.3017
34
1.2982
35
1.2502
21
1.2737
1
1.1590
1
1.2298
2
1.2300
2
1.2272
2
1.2252
2
1.1640
1
ROHF 1.2581
5
1.3291
15
1.3303
15
1.2743
13
1.2362
14
1.2359
14
1.2356
14
1.2243
14
1.2213
13
1.1777
5
1.1508
1
1.1579
1
1.2227
5
  1.2276
14
1.2266
14
1.1918
10
1.2197
12
1.2175
12
1.1968
9
  1.1541
1
1.2283
2
1.2317
2
1.2197
2
1.2174
2
 
density functional LSDA 1.3854
34
1.4265
33
1.4267
34
1.4069
33
1.3475
34
1.3479
34
1.3536
34
1.3407
34
1.3401
34
1.3384
33
1.2014
1
1.2014
1
1.3182
19
  1.3390
34
1.3394
34
1.2494
5
1.3421
33
1.3404
28
1.2568
4
  1.2078
1
1.2572
2
1.2565
2
1.2645
2
1.2609
2
 
BLYP 1.4281
36
1.4745
37
1.4782
38
1.4543
37
1.3542
46
1.3981
37
1.4015
36
1.4155
36
1.3914
35
1.3930
35
1.3632
2
1.2283
1
1.3501
20
1.5008
1
1.3951
38
1.3903
37
1.2295
1
1.3559
14
1.3423
11
1.2288
1
  1.2344
1
1.2943
2
1.2937
2
1.2989
2
1.2951
2
 
B1B95 1.3890
35
1.4495
33
1.4431
36
1.4106
35
1.3384
34
1.3348
35
1.3333
36
1.3268
35
1.3271
35
1.3235
32
1.3134
2
1.1916
1
1.3072
20
1.4382
1
1.3288
35
1.3276
35
1.2437
5
1.3198
32
1.3191
29
1.2413
5
  1.1958
1
1.2524
2
1.2520
2
1.2597
2
1.2580
2
 
B3LYP 1.4020
36
1.4500
38
1.4528
38
1.4224
37
1.3459
37
1.3458
37
1.3656
37
1.3375
37
1.3355
34
1.3389
39
1.3179
8
1.2033
1
1.3379
45
1.3293
51
1.3465
37
1.3435
36
1.3090
22
1.3488
34
1.3692
37
1.2946
20
1.1950
1
1.2082
1
1.2669
2
1.2666
2
1.2745
2
1.2728
2
1.2123
1
B3LYPultrafine 1.2853
1
1.4080
11
1.3005
1
1.2548
1
1.3394
33
1.3183
11
1.3029
14
1.3102
11
1.2056
1
1.3324
2
1.3304
2
1.2033
1
1.2988
12
1.4617
1
1.3235
20
1.3316
24
1.2041
1
1.3235
20
1.3273
40
1.2036
1
  1.2082
1
1.2669
2
1.2666
2
1.2746
2
1.2728
2
 
B3PW91 1.3893
34
1.4439
38
1.4466
38
1.4133
37
1.3321
36
1.3351
37
1.3340
37
1.3265
37
1.3246
34
1.3239
36
1.3198
2
1.1967
1
1.3120
20
1.4462
1
1.3321
38
1.3324
36
1.1975
1
1.3138
14
1.3207
13
1.1971
1
  1.2014
1
1.2582
2
1.2576
2
1.2655
2
1.2636
2
 
mPW1PW91 1.3874
33
1.4182
37
1.4217
35
1.4120
36
1.3267
36
1.3331
36
1.3283
37
1.3207
37
1.3253
36
1.3222
35
1.3134
2
1.1919
1
1.3074
20
1.4383
1
1.3272
36
1.3198
36
1.1927
1
1.3148
25
1.3158
23
1.1923
1
  1.1962
1
1.2530
2
1.2526
2
1.2604
2
1.2585
2
 
M06-2X 1.3706
23
1.4045
23
1.4052
48
1.3658
23
1.3199
39
1.3143
23
1.3133
23
1.3076
23
1.3081
23
1.3135
24
1.3077
2
1.1877
1
1.3053
21
1.4303
1
1.3096
23
1.3155
24
1.1880
1
1.3089
22
1.3161
23
1.1877
1
  1.1909
1
1.2490
2
1.2487
2
1.2560
2
1.2554
2
 
PBEPBE 1.4065
35
1.4666
36
1.4703
34
1.4427
33
1.3773
34
1.3733
35
1.3971
34
1.3835
35
1.3828
36
1.3745
35
1.3511
9
1.2172
1
1.3331
20
1.3375
51
1.3832
36
1.3762
35
1.2698
5
1.3797
23
1.3972
25
1.2791
4
  1.2226
1
1.2789
2
1.2783
2
1.2831
2
1.2777
2
1.2110
1
PBEPBEultrafine 1.3009
1
1.4239
11
1.3210
1
1.2747
1
1.3612
27
1.3296
11
1.3301
11
1.3244
11
1.2200
1
1.3466
2
1.3451
2
1.2172
1
1.3117
12
1.4766
1
1.3371
20
1.3367
20
1.2187
1
1.3356
20
1.3361
20
1.2179
1
  1.2227
1
1.2789
2
1.2783
2
1.2832
2
1.2778
2
 
PBE1PBE 1.3723
19
1.4006
18
1.4044
19
1.3672
19
1.3233
35
1.3139
19
1.3135
19
1.3055
19
1.3060
19
1.3068
19
1.3124
2
1.1916
1
1.3102
19
1.4367
1
1.3082
19
1.3087
19
1.1925
1
1.3078
19
1.3083
19
1.1921
1
  1.1957
1
1.2523
2
1.2519
2
1.2594
2
1.2577
2
 
HSEh1PBE 1.3803
22
1.4125
38
1.4104
22
1.3721
22
1.3237
38
1.3171
22
1.3222
38
1.3082
22
1.3087
22
1.3101
22
1.3135
2
1.1918
1
1.3069
20
1.4386
1
1.3110
22
1.3169
38
1.1927
1
1.3104
21
1.3112
21
1.1922
1
  1.1961
1
1.2529
2
1.2527
2
1.2601
2
1.2584
2
 
TPSSh 1.3925
9
1.3989
12
1.4032
12
1.3635
12
1.3349
41
1.3063
12
1.3345
41
1.2974
12
1.3246
9
1.3374
43
1.4636
1
  1.3029
12
1.4662
1
1.3007
12
1.3302
41
1.3269
8
1.3004
12
1.3019
12
1.3253
8
  1.2120
1
1.2711
2
1.2705
2
1.2785
2
1.2758
2
 
wB97X-D 1.3774
9
1.4029
9
1.3959
51
1.3669
9
1.3231
51
1.3137
9
1.3229
51
1.3058
9
1.3187
51
1.3073
9
1.4320
1
  1.3206
51
1.4351
1
1.3227
51
1.3183
51
1.3003
8
1.3068
9
1.3178
51
1.2988
8
  1.1983
1
1.1961
1
  1.2613
2
1.2597
2
 
B97D3 1.4031
7
1.4054
51
1.4266
7
1.3996
7
1.3450
51
1.3316
7
1.3462
51
1.3281
7
1.3417
51
1.3228
7
1.3528
51
  1.3306
7
1.4778
1
1.3308
7
1.3406
51
1.3224
7
1.3251
7
1.3649
50
1.3202
7
  1.2188
1
1.2157
1
  1.2818
2
1.2683
2
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 1.3991
33
1.4720
36
1.4745
36
1.4621
32
1.3393
48
1.3688
37
1.3689
38
1.3329
46
1.3490
37
1.3489
36
1.3364
2
1.2184
1
1.3451
45
1.3314
51
1.3559
38
1.3448
36
1.3100
20
1.3556
33
1.3514
29
1.3032
17
1.2664
1
1.3168
4
1.3104
5
1.2684
2
1.3017
2
1.2907
2
1.2155
1
MP2=FULL 1.3969
33
1.4688
34
1.4753
32
1.4640
29
1.3660
37
1.3680
37
1.3689
38
1.3435
38
1.3420
35
1.3473
34
1.3335
2
1.2156
1
1.3310
20
1.4587
1
1.3556
36
1.3441
34
1.3148
21
1.3353
25
1.3301
30
1.3003
17
1.2613
1
1.3159
4
1.3083
5
1.2663
2
1.3010
2
1.2846
2
1.2150
1
ROMP2 1.3632
10
1.4256
10
1.4256
10
1.4062
11
1.3064
12
1.3057
12
1.3081
12
1.2803
12
1.2815
12
1.2833
12
1.2458
1
1.2458
1
1.2851
6
  1.2885
12
1.2853
12
1.2285
2
1.2960
11
1.2349
4
1.2358
3
  1.2537
1
1.2803
2
1.2822
2
1.3333
2
1.3209
2
 
MP3 1.2929
1
1.2997
1
1.2997
1
1.2510
1
1.3477
34
1.2113
1
1.3341
42
1.1909
1
1.1909
1
1.1942
1
1.3114
2
1.1887
1
1.2871
12
1.4414
1
1.2870
12
1.2818
12
1.1879
1
1.2013
1
1.1926
1
1.1880
1
  1.1974
1
1.2517
2
1.2522
2
1.2685
2
1.2591
2
 
MP3=FULL   1.4132
9
1.4161
9
1.3878
9
1.3308
43
1.3258
9
1.3300
43
1.3034
9
1.3042
9
1.3067
9
1.4315
1
  1.2865
12
1.4389
1
1.2866
12
1.2780
12
  1.3173
9
1.2942
8
    1.1968
1
1.2500
2
1.2504
2
1.2680
2
1.2540
2
 
MP4 1.2851
1
1.4860
27
1.4464
3
1.4319
3
1.3723
33
1.2905
2
1.2930
2
1.3168
5
1.3515
28
1.2222
1
1.2208
1
1.2208
1
1.3469
19
  1.3400
19
1.3444
28
1.2216
1
1.3482
19
1.3375
18
1.2216
1
  1.2271
1
1.2766
2
1.2780
2
1.3052
2
1.2989
2
 
MP4=FULL 1.2851
1
1.4688
16
1.3618
1
1.3140
1
1.3532
19
1.2396
1
1.2416
1
1.2219
1
1.3319
19
1.2207
1
1.2182
1
1.2182
1
    1.3396
19
1.3347
19
1.2194
1
1.3478
19
1.3265
17
1.2193
1
  1.2265
1
1.2243
1
1.2760
2
1.3046
2
1.2925
2
 
B2PLYP 1.3755
12
1.4189
12
1.4230
12
1.3797
12
1.3372
31
1.3144
12
1.3125
14
1.2996
12
1.3013
13
1.3182
15
1.3354
2
1.2118
1
1.3091
12
1.4634
1
1.3039
12
1.3291
34
1.2126
1
1.3076
12
1.3212
15
1.2123
1
  1.2175
1
1.2715
2
1.2718
2
1.2886
2
1.2849
2
 
B2PLYP=FULL 1.3755
12
1.3771
14
1.4230
12
1.3797
12
1.3033
14
1.3141
12
1.3037
14
1.2993
12
1.2997
12
1.3029
12
1.4583
1
  1.3090
12
1.4627
1
1.3038
12
1.3056
12
  1.3075
12
1.3056
12
    1.2173
1
1.2710
2
1.2712
2
1.2884
2
1.2833
2
 
B2PLYP=FULLultrafine 1.3937
9
1.4425
9
1.4480
9
1.4091
9
1.3600
15
1.3409
9
1.3428
9
1.3255
9
1.3259
9
1.3300
9
1.4583
1
  1.3367
9
1.4627
1
1.3301
9
1.3338
9
  1.3345
9
1.3337
9
    1.2173
1
1.2143
1
  1.2884
2
1.2833
2
 
Configuration interaction CID 1.2779
1
1.4240
33
1.4249
33
1.3959
32
1.3350
37
1.2647
2
1.2652
2
1.3157
34
1.1861
1
1.1875
1
1.3003
2
1.1823
1
1.1917
1
1.4251
1
1.3148
3
1.3060
3
1.1810
1
1.1952
1
1.1858
1
1.1810
1
  1.1921
1
1.2454
2
1.2454
2
1.2606
2
1.2505
2
 
CISD 1.2781
1
1.4343
34
1.4350
34
1.4083
33
1.3385
37
1.3293
1
1.2696
2
1.3195
34
1.1898
1
1.1908
1
1.3040
2
1.1859
1
1.1957
1
1.4288
1
1.3196
3
1.3097
3
1.1846
1
1.1987
1
1.1893
1
1.1846
1
  1.1957
1
1.2493
2
1.2494
2
1.2650
2
1.2547
2
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Quadratic configuration interaction QCISD 1.4173
3
1.4827
34
1.4813
31
1.4488
33
1.3602
35
1.3680
35
1.3618
35
1.3457
35
1.3372
32
1.3364
32
1.2853
4
1.1995
1
1.3316
20
1.4527
1
1.3521
36
1.3215
30
1.1985
1
1.3447
23
1.3389
24
1.1986
1
  1.2080
1
1.2680
2
1.2690
2
1.2816
2
1.2722
2
 
QCISD(T) 1.2855
1
1.4049
2
1.4049
2
1.2850
1
1.3797
33
1.2918
2
1.3469
5
1.3193
10
1.3681
2
1.2125
1
1.2503
3
1.2093
1
1.3400
19
  1.3462
28
1.3395
28
1.2090
1
1.3360
23
1.3149
17
1.2091
1
  1.2165
1
1.2757
2
1.2773
2
1.2949
2
1.2857
2
 
QCISD(T)=FULL         1.3435
10
  1.3458
10
              1.3295
10
1.3176
10
1.3051
9
1.3363
10
1.3091
9
1.3008
7
  1.2159
1
1.2739
2
1.3386
1
1.2942
2
1.2798
2
 
QCISD(TQ)   1.3334
1
1.3334
1
1.2864
1
1.3424
9
1.2311
1
1.3441
9
1.2107
1
1.2107
1
1.2130
1
1.2089
1
1.2089
1
    1.3326
9
1.3126
9
1.2765
6
1.3356
9
1.2828
6
1.2796
2
             
QCISD(TQ)=FULL         1.3416
9
  1.3570
8
              1.3464
8
1.3199
8
1.3030
3
1.3348
9
1.2768
6
1.3475
1
             
Coupled Cluster CCD 1.4149
3
1.4419
34
1.4435
34
1.4224
34
1.3491
37
1.3518
34
1.3516
34
1.3334
35
1.3246
32
1.3259
32
1.2744
4
1.1919
1
1.3194
20
1.4439
1
1.3441
34
1.3177
29
1.1908
1
1.3287
28
1.3236
25
1.1909
1
  1.2015
1
1.2540
2
1.2544
2
1.2722
2
1.2623
2
 
CCSD 1.2843
1
1.3871
2
1.3871
2
1.3550
2
1.3467
34
1.3456
3
1.3510
6
1.3190
6
1.3975
4
1.3268
14
1.2824
4
1.1976
1
1.3286
20
1.4512
1
1.3370
24
1.3342
25
1.2942
16
1.3328
20
1.3263
22
1.2767
11
  1.2063
1
1.2632
2
1.2640
2
1.2803
2
1.2703
2
 
CCSD=FULL 1.2843
1
1.3169
1
1.3169
1
1.2708
1
1.3435
22
1.2194
1
1.2207
1
1.1992
1
1.1992
1
1.3260
14
1.3181
2
1.1951
1
1.3278
20
1.4484
1
1.3279
20
1.3230
22
1.2916
16
1.3323
20
1.3213
22
1.2754
12
  1.2056
1
1.2612
2
1.2620
2
1.2797
2
1.2648
2
 
CCSD(T) 1.2856
1
  1.3314
1
1.2834
1
1.3697
34
1.3340
10
1.3559
8
1.3091
10
1.2902
9
1.2783
7
1.2482
3
1.2083
1
1.3344
20
  1.3508
30
1.3339
30
1.2972
16
1.3494
27
1.3240
18
1.2793
11
  1.3134
4
1.3109
5
1.2750
2
1.2935
2
1.2843
2
 
CCSD(T)=FULL 1.2856
1
1.3313
1
1.3313
1
1.2833
1
1.3746
25
1.2287
1
1.2304
1
1.2090
1
1.2090
1
1.2103
1
1.2058
1
1.2058
1
1.3341
19
  1.3439
23
1.3293
21
1.2935
15
1.3506
22
1.3064
16
1.2731
10
  1.3126
4
1.3089
5
1.2732
2
1.2929
2
1.2784
2
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
daug-cc-pVDZ daug-cc-pVTZ daug-cc-pVQZ Sadlej_pVTZ CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.2272
2
1.2252
2
  1.1640
1
1.3617
35
1.3172
36
1.3606
35
1.3148
36
1.3586
35
1.3586
35
ROHF 1.2197
2
1.2174
2
    1.2167
1
1.1844
1
1.2144
1
1.1791
1
1.2073
1
1.2072
1
density functional LSDA 1.2645
2
1.2609
2
    1.2411
2
1.1968
2
1.2373
2
1.1896
2
1.2221
2
1.2219
2
BLYP 1.2989
2
1.2951
2
    1.3038
1
1.2576
1
1.3008
1
1.2529
1
1.2996
1
1.2996
1
B1B95 1.2597
2
1.2580
2
    1.3727
11
1.3147
12
1.2122
2
1.1689
2
1.2056
2
1.2056
2
B3LYP 1.2745
2
1.2728
2
  1.2123
1
1.4299
36
1.3647
36
1.4397
36
1.3615
36
1.4305
35
1.4270
36
B3LYPultrafine 1.2746
2
1.2728
2
    1.2757
1
1.2329
1
1.2728
1
1.2282
1
1.2684
1
1.2684
1
B3PW91 1.2655
2
1.2636
2
    1.2666
1
1.2243
1
1.2636
1
1.2192
1
1.2603
1
1.2602
1
mPW1PW91 1.2604
2
1.2585
2
    1.2601
1
1.2188
1
1.2571
1
1.2137
1
1.2539
1
1.2538
1
M06-2X 1.2560
2
1.2554
2
    1.2468
1
1.2089
1
1.2431
1
1.2023
1
1.2468
1
1.2466
1
PBEPBE 1.2831
2
1.2777
2
  1.2110
1
1.2900
1
1.2437
1
1.2870
1
1.2386
1
1.2872
1
1.2871
1
PBEPBEultrafine 1.2832
2
1.2778
2
    1.2900
1
1.2437
1
1.2870
1
1.2387
1
1.2872
1
1.2871
1
PBE1PBE 1.2594
2
1.2577
2
    1.2595
1
1.2180
1
1.2565
1
1.2128
1
1.2539
1
1.2538
1
HSEh1PBE 1.2601
2
1.2584
2
    1.2608
1
1.2188
1
1.2577
1
1.2137
1
1.2547
1
1.2546
1
TPSSh 1.2785
2
1.2758
2
               
wB97X-D 1.2613
2
1.2597
2
    1.3721
9
1.3298
9
1.3701
9
1.3269
9
1.3647
9
1.3650
9
B97D3 1.2818
2
1.2683
2
               
Moller Plesset perturbation MP2 1.3017
2
1.2907
2
  1.2155
1
1.4640
35
1.3861
36
1.4555
34
1.3826
36
1.4647
33
1.4623
33
MP2=FULL 1.3010
2
1.2846
2
  1.2150
1
1.3513
1
1.2637
1
1.3447
1
1.2587
1
1.3557
1
1.3554
1
ROMP2 1.3333
2
1.3209
2
    1.4249
1
1.2934
1
1.4186
1
1.2895
1
1.4484
1
1.4485
1
MP3 1.2685
2
1.2591
2
    1.2789
1
1.2307
1
1.2698
1
1.2236
1
1.2673
1
1.2667
1
MP3=FULL 1.2680
2
1.2540
2
               
MP4 1.3052
2
1.2989
2
    1.3184
1
1.2559
1
1.3183
1
1.2529
1
1.3244
1
1.3246
1
MP4=FULL 1.3046
2
1.2925
2
    1.3184
1
1.2559
1
1.3183
1
1.2529
1
1.3243
1
1.3244
1
B2PLYP 1.2886
2
1.2849
2
    1.3003
1
1.2445
1
1.2970
1
1.2400
1
1.2972
1
1.2971
1
B2PLYP=FULL 1.2884
2
1.2833
2
               
B2PLYP=FULLultrafine 1.2884
2
1.2833
2
               
Configuration interaction CID 1.2606
2
1.2505
2
    1.2754
1
1.2235
1
1.2679
1
1.2169
1
1.2663
1
1.2659
1
CISD 1.2650
2
1.2547
2
    1.2801
1
1.2268
1
1.2729
1
1.2204
1
1.2719
1
1.2714
1
Quadratic configuration interaction QCISD 1.2816
2
1.2722
2
    1.2957
1
1.2401
1
1.2896
1
1.2344
1
1.2901
1
1.2898
1
QCISD(T) 1.2949
2
1.2857
2
    1.3029
1
1.2478
1
1.2977
1
1.2428
1
1.2993
1
1.2990
1
QCISD(T)=FULL 1.2942
2
1.2798
2
               
QCISD(TQ)         1.3066
1
1.2498
1
1.3004
1
1.2441
1
1.3025
1
1.3021
1
Coupled Cluster CCD 1.2722
2
1.2623
2
    1.2871
1
1.2334
1
1.2801
1
1.2273
1
1.2798
1
1.2794
1
CCSD 1.2803
2
1.2703
2
    1.2932
1
1.2386
1
1.2871
1
1.2327
1
1.2870
1
1.2867
1
CCSD=FULL 1.2797
2
1.2648
2
    1.2932
1
1.2386
1
1.2871
1
1.2327
1
1.2869
1
1.2865
1
CCSD(T) 1.2935
2
1.2843
2
    1.3019
1
1.2471
1
1.2965
1
1.2420
1
1.2980
1
1.2977
1
CCSD(T)=FULL 1.2929
2
1.2784
2
    1.3019
1
1.2471
1
1.2965
1
1.2420
1
1.2979
1
1.2975
1
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.